A display device is a device for displaying a frame such as a text, a numeral, a symbol, a picture, or an image formed by combination of at least two of a text, a numeral, a symbol, a picture. The display device may be a flat display device, a curved surface display device, a 3D display device, a near eye display device, an AR/VR display device, and the like.
With the development of display devices, there is an increasingly high requirement on on-spot effect and viewer's sense of immersion. In order to improve the on-spot effect and viewer's sense of immersion, one of the key technology is for effective control of propagation of light within the display device. For example, a display device for performing a virtual display has a fixed central area of the view field and a non-central area of the view field. When a viewer is located within the viewing area before the display device and watches a frame displayed by the display device, the viewer's sight is focused on the central area of the view field. Propagation of light within the display device is controlled such that the viewer sees the frame as if it were projected on a virtual screen in front of the display device or behind the display device, and also the viewer can see the frame in both of the central area of the view field and the non-central area of the view field. Therefore, the display device may have a good on-spot effect and may improve the viewer's sense of immersion.
At present, generally, a microprism or a microlens may be provided to the display device, to realize the control of the propagation of light in the display device. That is, the conventional display device generally utilizes a structure based on geometrical optics principle to achieve control of the propagation of light in the display device. However, with the development of virtual display devices, structure based on geometrical optics principle is not sufficient to satisfy the requirement for control of the propagation of light within the display device, resulting in poor on-spot effect in the display performed by display device and poor sense of immersion for the viewer, thus bring a bad viewing experience for the viewer.